The roof garden is just one component of 2wise2waste, but it also has multiple functions. Firstly, only plants indigenous to the Western Cape will be used, arranged in areas according to vegetation types, such as succulent karoo, strandveld, coastal thicket and others. This garden will be a green space in the city, a small refuge for wildlife, even if only insects and birds. It will provide oxygen, absorb noise and use rain, which helps reduce the runoff from the roof that otherwise can make the city's drains overflow and flood roads. The garden will also moderate temperatures in the building, keeping it cooler in summer and warmer in winter, thereby saving on air-conditioning costs.
The roof garden is going to be an educational space where staff can see the vegetation types and plant species that they read about in EIA's (environmental impact assessments). It will also demonstrate the use of recycled materials in its construction, and hopefully will be able to use rainwater to irrigate, at least part of the time. The thermal regulation that a roof garden provides is also an aspect of green building design, something the Department is promoting. The garden will be visible to office workers in adjacent buildings, improving their urban view, but also sending out a message about sustainability.
Look out for signs of activity on the roof of 3 Dorp Street in the next few months. It's not as simple as just laying down soil and putting in plants. There is waterproofing, drainage, safety barriers and other things that need construction first, but keep an eye out and you will learn something as you see it happen. 2wise2waste will be rolling out to other departments in the years to come, things like recycling, energy saving appliances and green procurement policy, so start thinking green as we make our roof green.
For further information, please contact Roger Diamond Tel: 021 483 2901 of the Pollution and Waste Management Directorate.
